Improvement in sheaves



ilrtizt ttte ALVIN MATTHEW GUSHING,

0F LYNN MASSAClIUSETTS.

Letters Patent No. I109,184, dated 'November 15, 1870.

IMPROVEMENT IN'SHEAVES.

The Schedule referred to in" these Letters Patent and making part of the same.

ment in She'aves, or wheels provided with frictionrollers or balls; and do hereby declare the same to -he`fnlly described in the following specification and represented in the accompanying drawing, of which- Figure l is a side View;l Figure 2, a longitudinal section; and 4 Figure 3, a transverse section of a sheave as -containing my invention.

The said sheave, shown at A, has arranged within it coucentrically a cylindrical chamber, a, for containing a series ot' friction-rollers or spheres, b b b, and also a steel ring, c.A

The said ring encompassing the balls constitutes a bearing for them to Vrun against, and is separate from the body of the sheave.

-The ring is to yit closely to the periphery of the cavity or chamber a for its reception.

lhe bottom of the chamber a has an opening, d, to

receive the spindle or arbor-on which the sheave is to be supported when in use.

The chamber, at its top or opposite end, is open and furnished with a cap-plate, B, the ball or frictionwheel chamber being partially formed iu the cap-plate or not. g

This cap-plate is secured to the sheavc-bod y by screws e c e, or other proper fastenings, and has au annular projection, f, extendedy from its rearv side to enter a corresponding socket or groove, g, going around the steel ring7 but having a depth less than that of the said ring, the whole being as represented in the drawing. l

In the common way of applying a series of frictionrollers or balls to a pulley-sheave or a wheel, such friction-devices have been allowed to run directly as set forth.

aga-inst the circumference of the chamber for their reception, and when such has been made of cast-iron, and even when so made and chill-hardened, it would be liable to soon-become injuriously worn by the balls or rollers, and frequently cause them to stop and not perform their proper functions. Y

By having a separate bearing-ring of steel placed and titted closely in the cast-metal chamber, in manner as represented, such ring, when worn, may easily be removed, and another or fresh one be substituted, without the necessity of abandoning the sheave-body.

Ifur'thermore, the annular cavity about the ring enables such ring, after having been driven down into it's chamber', to be easily taken hold of by 'nippers when it may be desir( ble to disengagc the ring from .the chamber.

As the ring byuse is liable to be expanded more or less, it will generally so rmly tit the chamber as to render it difficult of removal therefrom without the accompaniment of the encircling cavity to aid in effecting such.

Furthermore, the said cavity and the projection f, from the cap or cover, serve to keep the cap or cover in place, and prevent strains on it from breaking or starting its confining screws, the projection .also answering as a support forthe ring.

,I claim as of my invention in the above-described sheave the following; that is to say- The arrangement and combination of the annular channel or groove g and projection f, with the capplate B, the ring c, the series ot'rcllers or balls b, and their chamber a, made in the body A of the sheave,

ALVIN MATTHEW GUSHING.

Witnesses R. H. EDDY, J. It. SNOW. 

